Jami Jokinen wrote:

I contacted the seller of the al-flagpole (dimensions in the earlier posts). He said it is T6 alloy.

What will the total length of your mast be, Jami?

Arne

hi annie

Annie Hill wrote:

…Marcus is making his mast with a 6m tube and (because he is sensitised to epoxy and can't work with it) he is having a carbon reinforced/glass fibre topmast made.

he should take care about the separation/isolation of the two sections – as i learned from jra people, combinations of carbon fibres and aluminium can lead to electrolytic corrosion.

utnik

I'll have to check with the supplier, if 6082 is available for all - if not right away, maybe before spring anyway :)


The supplier unfortunately has informed only the weight of 140/5. It is 6 kg/m.

Edit - I found info from another supplier:

130/5 - 5,32 kg/m 
140/5 - 5,75 kg/m (I have no idea why this is different than 140/5 above).

Edit 2: I forgot the tapered flagpole. It is 145mm/2.5mm (parallel, 2.8m, 60mm at the top, total length 12m -> two meters could be cut off.) I don't know yet, whether this is T5 or T6, but David suspects it has to be T5.

I quote the supplier: "It's either EN AW-6060 T6 , EN AW-6005A T6  or EN AW-6082 T6."

Apparently it depends on the situation at the warehouse, the excact size of the tube and possibly on the time of the purchase (which one is available and when).

Arne Kverneland wrote:

Jami,

Do you know want alloy (temper) is used in those aluminium tubes?

Now I have guesstimated the maximum stability of your boat to be about 715kpm (+/- 10%?). I would aim for a mast with a yield strength (bending moment) of about twice that.

Arne

The straight tubes are T6.  What does the double yield strength mean in case of straight 130-160 mm T6 tubes?

(I'm a biologist and a journalist and a bit of a musician, not a technician or engineer, so this is all very complicated and strange to me...)